Dan Aykroyd appeared on The Dennis Miller Show to discuss the project, dropping specific details about the sequel, hinting that the plan is to film in Spring of 2012 no matter what happens casting-wise.

"Yes, we will be doing the movie and hopefully with Mr. Murray," he says, "That is our hope. We have an excellent script. What we have to remember is that 'Ghostbusters' is bigger than any one component, although Billy was absolutely the lead and contributive to it in a massive way, as was the director and Harold [Ramis], myself and Sigourney [Weaver]. The concept is much larger than any individual role and the promise of 'Ghostbusters 3' is that we get to hand the equipment and the franchise down to new blood."

The comedian also confirmed reports that the plot will revolve around a new generation of Ghostbusters and hinted at the states of his and Ramis' characters.

"My character, Ray, is now blind in one eye and can't drive the cadillac," he says, "He's got a bad knee and can't carry the packs... Egon is too large to get into the harness. We need young blood and that's the promise. We're gonna hand it to a new generation."

As for who might be cast as the new characters, Aykroyd says that, while no decision has been made, he does have a fondness for one piece of prospective casting.

"I like this guy Matthew Gray Gubler from the 'Criminal Minds' show," he adds, "But there's going to be a casting. We're going to see everyone that wants to do it. We're going to need... three guys and a young woman."http://www.comingsoon.net/news/movienews.php?id=81518

Ghostbusters I and II were great movies that were my favorites growing up

But I hope they don't make a 3rd one, I think it'll suck. I think the cast is too out of touch to pull off a strong comedy performance (just by watching interviews like Aykroyd on Jimmy Kimmel or Murray on Letterman). They don't have the funny anymore.

and I'll place a bet that Murray won't sign on to do it. Didn't I hear that he was tired of comedy? Plus didn't he and Harold Ramis have a huge disagreement over Groundhog Day and said they would never work together again?

Ghostbusters I and II were great movies that were my favorites growing up

But I hope they don't make a 3rd one, I think it'll suck. I think the cast is too out of touch to pull off a strong comedy performance (just by watching interviews like Aykroyd on Jimmy Kimmel or Murray on Letterman). They don't have the funny anymore.

and I'll place a bet that Murray won't sign on to do it. Didn't I hear that he was tired of comedy? Plus didn't he and Harold Ramis have a huge disagreement over Groundhog Day and said they would never work together again?

What??? The second Ghostbusters movie was absolute dogshit. Why do you suppose they waited this long to make a 3rd movie? Easy answer: because the second one was a big failure and a massive disapointment, financially. Hollywood is starving for new ideas and movie concepts so it was only a matter of time before a 3rd Ghostbusters movie came out. This one will be a failure also if Bill Murray isn't in it.

What??? The second Ghostbusters movie was absolute dogshit. Why do you suppose they waited this long to make a 3rd movie? Easy answer: because the second one was a big failure and a massive disapointment, financially. Hollywood is starving for new ideas and movie concepts so it was only a matter of time before a 3rd Ghostbusters movie came out. This one will be a failure also if Bill Murray isn't in it.

I prefer the second one lol. I thought it did pretty good financially? I remember reading Bill Murray hated it.

We've heard it again and again and again over the years due to Bill Murray holding up production, however now Ivan Reitman and Dan Aykroyd have confirmed that Ghostbusters 3 is under way. Deadline is now reporting that the Reitman helmed film Draft Day has been postponed in order to alot enough time for Reitman to finish pre-production on Ghostbusters 3. Last we heard from Aykroyd was this:

“We’ve got a brilliant new writer on it and we’ll be passing the torch on to a new generation. We’re working on it to make it just right to satisfy our fans. I’m confident we’ll be in production in the next year.”

Production on the film is to begin Summer of 2013... you can read more at screenrant.com

It's still unclear if Murray will reprise his role as Peter Venkman. Murray says it's still a possibility but Aykroyd has stated that Ghostbusters 3 will be moving forward without him, and that the original Ghostbusters will be passing the torch.